1. Field of the Invention
The present invention relates to an on-load tap changer for regulating the voltage on a transformer while energized or on load which is of the type that includes a tap selector and a diverter switch. The central part of the tap selector includes support means for movable selector contacts for providing a connection between fixed contacts mounted in a circle on outer support means and current collector rings which are electrically connected to the diverter switch and which surround the central support means. The fixed contacts are arranged in through-holes in the outer support means such that both end portions of each contact extend on both sides of the support means, one end portion forming a contact part for cooperation with one of the movable contacts, the other end portion constituting a terminal intended to be electrically connected to one tap of a regulating transformer winding.
2. The Prior Art
From German Patent Document 2 945 724 an on-load tap changer that includes a tap selector and a diverter switch is previously known, in which the support means for the movable contacts of the tap selector consists of two parallel rods of insulating material which are placed inside the current collector rings of the tap selector. The fixed contacts of the tap selector are mounted on insulating bars which are arranged in parallel with and in a circle around the common axis of rotation of the two inner rods. The fixed contacts are fixed to the insulating bars by forming the end portion of the respective contact, after the contact has been placed in a through-hole in the bar, by transversal upsetting into a flat connection member which projects in the radial direction outside the hole.
From German Patent Document 2 105 604 an off-circuit tapping switch is previously known, in which the fixed contacts are fixed by upsetting to a cylindrical tube provided with mounting and inspection openings.